A catalyst comprising
(i) an asymmetric complex of formula (I)
wherein
M is zirconium or hafnium;
each X is a sigma ligand;
L is a divalent bridge selected from -R'2C-, -R'2C-CR'2-, -R'2Si-, -R'2Si-SiR'2-, -R'2Ge-, wherein each R' is independently a hydrogen atom, C1-C20-alkyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl;
R2 and R2' are each independently linear C1-10 hydrocarbyl;
R5 and R5' are each independently hydrogen or a C 1-20 hydrocarbyl group;
R6 and R6' are each independently hydrogen or a C1-20 hydrocarbyl group;
R7 is hydrogen or a C1-20 hydrocarbyl group or is ZR3;
Z is O or S, preferably O;
R3 is a C1-10 hydrocarbyl group;
Ar is an aryl or heteroaryl group having up to 20 carbon atoms optionally substituted by one or more groups R8;
Ar' is an aryl or heteroaryl group having up to 20 carbon atoms optionally substituted by one or more groups R8';
R8 and R8' are each independently is a C1-20 hydrocarbyl group;
with the proviso that at least one of R6 or R7 is not H;
and (ii) a cocatalyst comprising a compound of a group 13 metal, e.g. boron.
一种催化剂,包括
(i) 式(I)的不对称络合物
其中
M 是
锆或
铪
每个 X 是σ
配体;
L 是选自-R'2C-、-R'2C-CR'2-、-R'2Si-、-R'2Si-SiR'2-、-R'2Ge-的二价桥,其中每个 R'独立地为氢原子、C1-C20-烷基、三(C1-C20-烷基)
硅烷基、C6-C20-芳基、C7-C20-芳基烷基或 C7-C20-烷基芳基;
R2 和 R2'各自独立地为线性 C1-10 烃基;
R5 和 R5'各自独立地为氢或 C1-20 烃基;
R6和R6'各自独立地为氢或C1-20烃基;
R7 是氢或 C1-20 烃基或 ZR3;
Z 是 O 或 S,最好是 O;
R3是C1-10烃基;
Ar 是具有多达 20 个碳原子的芳基或杂芳基,可任选被一个或多个基团 R8 取代;
Ar' 是具有多达 20 个碳原子的芳基或杂芳基,可选择被一个或多个基团 R8' 取代;
R8和R8'各自独立地为C1-20烃基;
但 R6 或 R7 中至少有一个不是 H;
和(ii) 由第 13 族
金属(如
硼)化合物组成的助催化剂。